The invention relates to novel compounds that are useful additives to functional fluids. By the term "functional fluids" is meant fluids commonly adapted for the transfer of mechanical or thermal energy including hydraulic fluids, for example, fluids employed in braking systems of automobiles, trucks and military vehicles, power steering systems and actuating devices and controls for automobiles, airplanes, ships; shock absorbing devices, jacks and door closures, etc. Also included are heat absorbing and transporting fluids for use in transformers and other electrical or mechanical devices. In particular the fluids are those designed to remain essentially anhydrous or if contaminated by small quantities of water, as for example, by absorption from contact with the atmosphere, the fluids should remain substantially unaffected in their desired qualities.
It is customary, in order to provide a fluid suitable for use as a functional fluid, to incorporate into the formulation of such a fluid a water-scavenging agent capable of reacting with small amounts of water so as to render the fluid unaffected by contamination with water.
A further desirable additive for functional fluid compositions are corrosion inhibitors, in particular compounds useful in reacting with acids such that the fluid retains a neutral or slightly alkaline pH. A functional fluid so designed has been found to be less likely to promote corrosion and premature failure of metal parts in contact with the fluid.
Amide acetals were first reported by Meerwein, Angew. Chem., 71, 530 (1959) who taught that the compounds were quite versatile, highly reactive intermediates.
In U.S. Pat. No. 3,092,637, acetals and ketals of N,N-disubstituted carboxyamides of the formula ##STR2## wherein R', R", R''' and R"" are specified hydrocarbyl radicals and R is hydrogen or hydrocarbyl, are disclosed. Also taught is a process for making the compounds by reacting an alkali metal or alkaline earth metal salt of an alcohol or phenol with a 1,1-dihalosubstituted tertiary amine.
It is known that amide acetals exchange oxygen-containing functionalities upon heating with higher boiling alcohols and phenols. The compounds also condense without a catalyst with compounds containing a labile methyl or methylene to form corresponding methylene amine compounds.